HTML5 / CSS3 Circle with Partial Border Is Not Possible?

In HTML5 and CSS3, creating a circle with a partial border using pure DOM elements is not directly possible. However, there are techniques to achieve a similar effect:

CSS Mask Method

The CSS mask method involves using two layers of masks:

1. Conic Gradient Mask: Creates a visible pie selection relative to the border-box.
2. Full Cover Mask: Restricts the top layer to the padding-box.

This approach allows you to achieve a partial border without additional elements or JavaScript.

Canvas Drawing Method

Alternatively, you can draw the circle with a partial border using canvas:

1. Create a canvas element.
2. Use the canvas drawing API to create a circle and draw a partial arc to mimic the border.

SVG Method

SVG (Scalable Vector Graphics) allows you to create circles and specify partial borders:

1. Define an SVG circle element.
2. Use the stroke-dasharray and stroke-dashoffset attributes to create the partial border.

HTML5 with JavaScript Method

With HTML5 and JavaScript, you can dynamically create a circle and modify its border:

1. Create a DOM element (e.g., a div) to represent the circle.
2. Use JavaScript to apply a partial border using CSS properties (border, border-radius, and clip-path).

The specific technique you choose will depend on factors such as browser support, performance, and the level of detail required.